TF10158: The user or group name XXXX contains unsupported characters, is empty, or too long.

From TFS 2017 Upgrade, TFS Access Level is not accepting the AD groups with (&) ampersand which used to be allowed till the previous release. We get the error post upgrade and when we tried to add a new group to the Access Level.

TF10158: The user or group name XXXXXXXX contains unsupported characters, is empty, or too long.

Thank you for your feedback! Unfortunately, right now we don't have enough information to investigate this issue and find a solution. If this is still an issue for you, please update to our latest version. If you are still able to repro it, please provide us with more info! Thank you for helping us build a better Visual Studio!

We have already tried example strings like the one that you showed, but were unable to reproduce the error you're describing. To continue to debug this, we need your exact group name and the TFS complete version number. Thank you so much again!